kelredd-pruview gem 0.3.8 for Ruby allows context-dependent attackers to execute arbitrary commands via shell metacharacters in a filename argument to (1) document.rb, (2) video.rb, or (3) video_image.rb.
lib/ldoce/word.rb in the ldoce 0.0.2 gem for Ruby allows remote attackers to execute arbitrary commands via shell metacharacters in (1) an mp3 URL or (2) file name.